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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
51

Well Owners' Guide to Ground Water Resources in Gila County

Uhlman, Kristine, Jones, Chris, Hill, Rachel 11 1900 (has links)
6 pp. / Well Owners' Guide to Ground Water Resources in Yavapai County. AZ1451 / Private well owners are responsible for the safety and quality of their water supply. The nearly 6,000 exempt wells in Gila County are not regulated by any state or federal agency, and lot splits and subdivisions may result in an unregulated water supply serving several homes. This publication is one in a series of county-based publications that identifies well maintenance and testing procedures for the well owner, with an emphasis on water quality concerns for Gila County.
52

Nitrate Contamination Potential in Arizona Groundwater: Implications for Drinking Water Wells

Uhlman, Kristine, Artiola, Janick 07 1900 (has links)
4 pp. / This fact sheet is to be taken from research conducted by Uhlman and Rahman and published on the WRRC web site as: "Predicting Ground Water Vulnerability to Nitrate in Arizona". Funded by TRIF and peer reviewed by ADEQ. It also follows on "Arizona Well Owner's Guide to Water Supply" and also "Arizona Drinking Water Well Contaminants" (part 1 already submitted, part 2 in process). / Arizona's arid environment and aquifer types allow for the persistence of nitrate contamination in ground water. Agricultural practices and the prevalence of septic systems contributes to this water quality concern, resulting in nitrate exceeding the EPA Maximum Contaminant Level (MCL) in several locations across the state. Working with known nitrate concentrations in 6,800 wells across the state, this fact sheet presents maps showing the probability of nitrate contamination of ground water exceeding the MCL. The importance of monitoring your domestic water supply well for nitrate is emphasized.
53

Up-scaling hydrological processes and the development of a large-scale river basin modelling system

Sloan, William Taylor January 1999 (has links)
No description available.
54

Numerical modelling of groundwater flow and radioactive waste migration : Sellafield, England

Wu, Kejian January 1999 (has links)
No description available.
55

Sensitivity studies with a surface and channel runoff module coupled to a mesoscale atmospheric model

Mölders, Nicole, Rühaak, Wolfram 06 December 2016 (has links) (PDF)
A module to investigate ground water recharge was developed, and implemented into the mesoscale meteorological model GESIMA (Geesthacht’s simulation model of the atmosphere) as well as coupled to a soil-vegetation scheme. Important features of the ground water module are the determination of surface and channel runoff. A comparison of the results provided by GESIMA with and without consideration of surface and channel runoff shows a remarkable impact of surface runoff on the soil moisture fluxes. Substituting water meadows by willow-forests demonstrates their importance for soil moisture fluxes. / Ein Modul zur Untersuchung von Grundwasserneubildung wurde entwickelt, in das mesoskalige meteorologische Modell GESIMA (Geesthachter Simulationsmodell der Atmosphäre) integriert und an ein Boden-Vegetationsmodell gekoppelt. Wesentliche Bestandteile des Grundwassermoduls sind die Berechnung des Oberflächen- und Gerinneabflusses. Ein Vergleich der Ergebnisse von GESIMA, die mit und ohne Oberflächen- und Gerinneabfluss erstellt wurden, belegt einen deutlichen Einfluss des Oberflächenabflusses auf die berechneten Feuchteflüsse im Boden. Untersuchungen zum Einfluss von Auenwäldern auf die Grundwasserneubildung belegen deren Bedeutung für die Wasserflüsse im Boden.
56

Investigação de aquífero fraturado para entendimento de fluxo e transporte de contaminantes clorados: estudo de caso em Valinhos, SP / not available

Fanti, Aline Campello 29 March 2016 (has links)
Casos de contaminação de aquíferos fraturados são bastante complexos, tendo em vista a heterogeneidade das redes de fraturas, e no geral, sua investigação demanda a utilização de técnicas pouco usuais, como por exemplo o imageamento acústico e a perfilagem de velocidade de fluxo de água. Na área de estudo, localizada em Valinhos/SP, o uso inadequado de solventes organoclorados no passado ocasionou a contaminação do aquífero raso em duas áreas, e o aparecimento de concentrações no aquifero profundo levaram a condução do atual trabalho, que teve como principal objetivo a elaboração de um modelo conceitual de fluxo de água e transporte de contaminantes no aquífero cristalino. Previamente à investigação do aquífero fraturado, foi realizada uma análise de trabalhos existentes, incluindo a interpretação de lineamentos, levantamentos geológicos além de perfilagens geofísicas de superfície. Em cada área investigada, foi realizada a perfuração de um poço profundo e aplicadas as técnicas de perfilagens de raios gama, cáliper, flowmeter, imageamento acústico, além da filmagem do poço e realização de ensaios hidráulicos nos dois pontos perfurados. Para caracterização química do aquífero fraturado, foram realizadas coletas de água subterrânea em intervalos selecionados com a utilização de obturadores pneumáticos. As cargas hidráulicas medidas durante a amostragem também auxiliaram no entendimento da direção do fluxo de água. O aquífero cristalino é formado por rochas gnáissicas e se encontra bastante fraturado e intemperizado, principalmente na porção superficial da rocha (até aproximadamente 65,0 m) onde as maiores velocidades de fluxo de água também foram observadas. A rocha sã possui uma menor densidade de fraturas e predominância de minerais mais claros. As fraturas de baixo a médio angulo de mergulho (Grupo 1) são as mais frequentes em ambas as perfurações e possuem direção principal N-S a NE-SW. São observadas, no geral, exercendo grande influência sobre o fluxo de água, principalmente na porção alterada do gnaisse. Fraturas com ângulo elevado de mergulho, classificadas como Grupo 2 (paralelas à foliação) e Grupo 3 (direção NW à W), são também observadas ao longo de toda a perfuração estabelecendo a conexão hidráulica entre as fraturas do Grupo 1. Em menor proporção, são ainda verificadas fraturas com ângulos de mergulho >40 ° pertencente aos Grupos 4 (NE-SW), 5 (E-W), 6 (NW-SE) e 7 (E-W). O fluxo de água subterrânea se mostrou descendente na porção superior da rocha alterada e ascendente na porção mais profunda, possivelmente direcionando a água subterrânea para a região de transição da rocha mais alterada para a rocha sã (entre 61 a 65 m de profundidade). Apesar do fluxo ascendente em profundidade, o bombeamento de poços tubulares existentes no entorno ao longo dos anos, favoreceu a migração dos contaminantes para porções mais profundas. Os contaminantes observados no poço tubular P6 possuem maior semelhança com os contaminantes observados na Área 2, e ambos estão localizados entre lineamentos NW-SE, indicando uma possível influência dos lineamentos no controle sobre o fluxo de água. No entanto, para entendimento do transporte dos contaminantes em área, é necessário um adensamento da rede de monitoramento, levando em consideração a heterogeneidade do meio e as incertezas relacionadas à extrapolação dos dados para áreas não investigadas. / Cases of contamination in fracture aquifers are complex, given the heterogeneity of the fractures network and the common requirement of unusual techniques for investigation, such as the acoustic imaging and water flow velocity profile. In the study area, located in Valinhos / SP, the inappropriate use of organochlorine solvents in the past caused the contamination of the shallow aquifer in two areas, and the appearance of concentrations in the deep aquifer, lead to the current work, whose main goal was the development of a conceptual model of groundwater flow and contaminants transport in the crystalline aquifer. An analysis of pre-existing works, including the interpretation of lineaments, geological surveys as well as surface geophysical profiling, was conducted previously the investigation of fractured aquifer. A deep well was drilled in each area and applied the profiling methods gamma ray, caliper, flowmeter and acoustic imaging, as well as filming the wells and conducting hydraulic tests in two drillings. For chemical characterization of the fractured aquifer, groundwater sampling were collected at selected intervals with the use of pneumatic packers. Hydraulic heads measured during sampling also helped in understanding the direction of water flow. The crystalline aquifer is consisted by a fractured and weathered gneissic rock, especially in the upper portion of the rock (up to approximately 65.0 m) where higher water flow rates were observed. The fresh rock has a lower fracture density and predominantly lighter minerals. Fractures of low to medium dip angle (Group 1) are the most frequent in both boreholes. Their main direction is N-S to NE-SW, and they are in general, exerting great influence on the water flow, especially in the weathered portion of the gneiss. Fractures with high dip angle classified as Group 2 (parallel to foliation) and Group 3 (direction NW to W) are also observed throughout the drillings, establishing the hydraulic connection between the fractures from Group 1. At a lower frequency, fractures with dip angles >40 °, classified as groups 4 (direction NE-SW), 5 (E-W), 6 (NW-SE) and 7 (E-W), are verified. The water flow was downgradient in the surficial weathered portion of the rock, and upgradient in the deepest portion, probably directing the water flow to the transition portion of altered rock for the fresh rock (between 61 to 65 m in depth). Despite the upward flow in higher depth, pumping existing wells in the vicinity over the years favored the migration of contaminants into deeper portions of que aquifer. The compounds observed in the tubular well P6 have a greater resemblance to the contaminants observed in Area 2, and both are located between NW-SE lineaments, indicating a possible influence on control over the water flow and contaminant transport. However, a dense of monitoring network is necessary to understand the transport of contaminants in the study area, for which should be considered the proposed objectives, and taken into account the heterogeneity of the environment and the uncertainties related to extrapolation of data to non-investigated areas.
57

Utilização de águas salobras no cultivo da alface em sistema hidropônico NFT com alternativa agrícola condizente ao semi-árido brasileiro / Use of brackish waters for lettuce production in NFT hydroponics system as a suitable agricultural alternative to Brazilian semi-arid

Soares, Tales Miler 15 October 2007 (has links)
Muitas vezes, a agricultura extensiva falha sob as condições semi-áridas da região Nordeste do Brasil, onde há escassez de águas superficiais e as chuvas são irregulares. O uso de águas subterrâneas poderia melhorar a produtividade das culturas. Mas, devido à condição geológica, é freqüente a ocorrência de águas subterrâneas salobras. A utilização dessas águas levaria à salinização do solo. Além disso, os poços perfurados têm baixas vazões. Nesse cenário, a hidroponia pode ser condizente à produção intensiva, baseada em pequenas áreas. A eficiência do uso da água na hidroponia é reconhecidamente maior que no solo porque torna mínima a perda por evaporação. Além disso, a hidroponia poderia aumentar a tolerância das culturas à salinidade. Isso permitiria o uso de águas salobras e, como benefício extra, incrementaria a proteção ambiental. Em hidroponia, não há o potencial mátrico que leva à diminuição da energia livre da água. Também, a própria estrutura funciona como sistema de drenagem. Os sais acumulados ao final do processo produtivo podem ser facilmente dirigidos para fora do sistema. Com essa hipótese, foram conduzidos experimentos para avaliar a tolerância da alface (cultivar Verônica) à salinidade em hidroponia e em solo. Foi construída uma estrutura experimental (40 parcelas independentes) para simular o cultivo na técnica do fluxo laminar de nutrientes (NFT). Para o cultivo em solo, foram utilizados vasos de 12 L e mulch plástico. Foi observado que na hidroponia NFT é possível empregar águas mais salobras que no cultivo em solo. Quando se têm disponíveis água doce e salobra, pode ser mais interessante usar água doce no preparo da solução nutritiva e água salobra na reposição ao volume consumido. O uso de água salobra para o preparo da solução nutritiva e da água doce para a reposição ao consumo produziu maiores perdas relativas sobre o rendimento do que a salinização gradual. Esse resultado foi proporcionado pela precocidade da alface. Em relação à tolerância, a salinidade limiar da alface 'Verônica' cultivada em hidroponia NFT foi estimada em 4,03 dS m-1. Sob as mesmas condições experimentais, a tolerância em solo foi estimada em 2,51 dS m-1. Esses resultados confirmam a hipótese levantada e permitem apresentar uma alternativa agrícola condizente à realidade de muitas famílias isoladas no semi-árido brasileiro. / Several times, the extensive agriculture fails under semi-arid conditions in the Northeast region of Brazil, where the surface water is shortage and the pluvial precipitation is irregular. The use of groundwaters could increase the crops yield. However, due to the geological factors, it is usual the occurrence of brackish groundwaters in this region. The utilization of these waters would carry to soil salinization. Moreover, the opened deep tubewells often have low capacity. In this scenario, the hydroponics systems may be suitable to intensive production based in reduced areas. The higher water use efficiency in soilless cultivation is a well reported advantage, because in this system the water loss by evaporation is minimum. In hydroponics systems could be increase the crop salt tolerance. This would permit the brackish water use and, as an extra benefit, would increase the environmental safety. In hydroponics system, there is no the matric potential, which decreases the free-energy of water. Furthermore, the hydroponics structure operates as a drainage system. The accumulated salts, at the end of the period, may be easily removed from system. In order to test this hypothesis, were carried out experiments to evaluate the lettuce (cv. Verônica) salt tolerance under soil and hydroponics conditions. It was constructed a structure (40 independent experimental units) to simulate the Nutrient Technique Film (NFT) cultivation. For the soil experiment, it was used 12 L recipients and plastic mulch. It was registered that is feasible use waters more brackish in NFT system than in soil. For available of brackish and nonsaline waters, it was more productive to use non-saline water to prepare the nutrient solution and brackish water to supply the water consumption. Higher yield losses were observed with the use the brackish water to prepare nutrient solution and the non-saline water to replace the water consumption. The nutrient solution salinization was less depreciative to yield than the constant salinity. This finding was providing by the lettuce precocity. In relation to the salt tolerance in NFT system, the lettuce salinity threshold was estimated in 4.03 dS m-1. Under the same experimental conditions, the tolerance in soil was estimated in 2.51 dS m-1. These results confirmed the hypothesis and permit to present an agricultural alternative suitable to reality of many isolated families in Brazilian semi-arid.
58

Utilização de águas salobras no cultivo da alface em sistema hidropônico NFT com alternativa agrícola condizente ao semi-árido brasileiro / Use of brackish waters for lettuce production in NFT hydroponics system as a suitable agricultural alternative to Brazilian semi-arid

Tales Miler Soares 15 October 2007 (has links)
Muitas vezes, a agricultura extensiva falha sob as condições semi-áridas da região Nordeste do Brasil, onde há escassez de águas superficiais e as chuvas são irregulares. O uso de águas subterrâneas poderia melhorar a produtividade das culturas. Mas, devido à condição geológica, é freqüente a ocorrência de águas subterrâneas salobras. A utilização dessas águas levaria à salinização do solo. Além disso, os poços perfurados têm baixas vazões. Nesse cenário, a hidroponia pode ser condizente à produção intensiva, baseada em pequenas áreas. A eficiência do uso da água na hidroponia é reconhecidamente maior que no solo porque torna mínima a perda por evaporação. Além disso, a hidroponia poderia aumentar a tolerância das culturas à salinidade. Isso permitiria o uso de águas salobras e, como benefício extra, incrementaria a proteção ambiental. Em hidroponia, não há o potencial mátrico que leva à diminuição da energia livre da água. Também, a própria estrutura funciona como sistema de drenagem. Os sais acumulados ao final do processo produtivo podem ser facilmente dirigidos para fora do sistema. Com essa hipótese, foram conduzidos experimentos para avaliar a tolerância da alface (cultivar Verônica) à salinidade em hidroponia e em solo. Foi construída uma estrutura experimental (40 parcelas independentes) para simular o cultivo na técnica do fluxo laminar de nutrientes (NFT). Para o cultivo em solo, foram utilizados vasos de 12 L e mulch plástico. Foi observado que na hidroponia NFT é possível empregar águas mais salobras que no cultivo em solo. Quando se têm disponíveis água doce e salobra, pode ser mais interessante usar água doce no preparo da solução nutritiva e água salobra na reposição ao volume consumido. O uso de água salobra para o preparo da solução nutritiva e da água doce para a reposição ao consumo produziu maiores perdas relativas sobre o rendimento do que a salinização gradual. Esse resultado foi proporcionado pela precocidade da alface. Em relação à tolerância, a salinidade limiar da alface 'Verônica' cultivada em hidroponia NFT foi estimada em 4,03 dS m-1. Sob as mesmas condições experimentais, a tolerância em solo foi estimada em 2,51 dS m-1. Esses resultados confirmam a hipótese levantada e permitem apresentar uma alternativa agrícola condizente à realidade de muitas famílias isoladas no semi-árido brasileiro. / Several times, the extensive agriculture fails under semi-arid conditions in the Northeast region of Brazil, where the surface water is shortage and the pluvial precipitation is irregular. The use of groundwaters could increase the crops yield. However, due to the geological factors, it is usual the occurrence of brackish groundwaters in this region. The utilization of these waters would carry to soil salinization. Moreover, the opened deep tubewells often have low capacity. In this scenario, the hydroponics systems may be suitable to intensive production based in reduced areas. The higher water use efficiency in soilless cultivation is a well reported advantage, because in this system the water loss by evaporation is minimum. In hydroponics systems could be increase the crop salt tolerance. This would permit the brackish water use and, as an extra benefit, would increase the environmental safety. In hydroponics system, there is no the matric potential, which decreases the free-energy of water. Furthermore, the hydroponics structure operates as a drainage system. The accumulated salts, at the end of the period, may be easily removed from system. In order to test this hypothesis, were carried out experiments to evaluate the lettuce (cv. Verônica) salt tolerance under soil and hydroponics conditions. It was constructed a structure (40 independent experimental units) to simulate the Nutrient Technique Film (NFT) cultivation. For the soil experiment, it was used 12 L recipients and plastic mulch. It was registered that is feasible use waters more brackish in NFT system than in soil. For available of brackish and nonsaline waters, it was more productive to use non-saline water to prepare the nutrient solution and brackish water to supply the water consumption. Higher yield losses were observed with the use the brackish water to prepare nutrient solution and the non-saline water to replace the water consumption. The nutrient solution salinization was less depreciative to yield than the constant salinity. This finding was providing by the lettuce precocity. In relation to the salt tolerance in NFT system, the lettuce salinity threshold was estimated in 4.03 dS m-1. Under the same experimental conditions, the tolerance in soil was estimated in 2.51 dS m-1. These results confirmed the hypothesis and permit to present an agricultural alternative suitable to reality of many isolated families in Brazilian semi-arid.
59

Bergvärme som energikälla

Back, Natalii January 2008 (has links)
<p>2008-05-26</p><p>Bedrock heat as an energy source</p><p>The sun has warmed up the bedrock and this heat can be used for warming up houses. Approximately 100 – 200 meters down in the bedrock the temperature of the heat is stable. This is a source of energy that can be used by installing a heat pump system. The ground source heat pumps are low maintenance and can last for many years. There is also a pollution risk for the groundwater and therefore the wells in the area. Before the ground source heat pump can be installed the municipality need to give permission, according to the environmental code. To install the system without permission is a crime against the environmental code. A requirement when applying for permission to install the heat pump system is to get the neighbours to agree with the place for the bore hole. The neighbour can appeal against the environmental and health authorities’ decision to give permission to install the ground source heat pump system. However there needs to be more research done regarding the environmental effects that may occur in the future, if the ground source heatpump system continues to increase as rapidly as today.</p>
60

Bergvärme som energikälla

Back, Natalii January 2008 (has links)
2008-05-26 Bedrock heat as an energy source The sun has warmed up the bedrock and this heat can be used for warming up houses. Approximately 100 – 200 meters down in the bedrock the temperature of the heat is stable. This is a source of energy that can be used by installing a heat pump system. The ground source heat pumps are low maintenance and can last for many years. There is also a pollution risk for the groundwater and therefore the wells in the area. Before the ground source heat pump can be installed the municipality need to give permission, according to the environmental code. To install the system without permission is a crime against the environmental code. A requirement when applying for permission to install the heat pump system is to get the neighbours to agree with the place for the bore hole. The neighbour can appeal against the environmental and health authorities’ decision to give permission to install the ground source heat pump system. However there needs to be more research done regarding the environmental effects that may occur in the future, if the ground source heatpump system continues to increase as rapidly as today.

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